About a month ago, approximately once per week, my 2004 Mazda RX-8 automatic has begun to violently shudder so badly that once on the highway I was towed to a garage after hours but after the tow/wait of 2 hours, it drove fine. The other times I was still in my city and gently got it home where after an hour or so, it drove fine. A few of the incidents featured a brief metallic grinding sound when the shaking began. All times had a foul hot grinding metal smell. The shaking does not occur when car is idling. It happens at all speeds/gears once it starts. One time happened at 100km/hr while other times at 50km/hr. I can drive it for a week without incident but can’t trust it for long distances outside of city for fear of another tow.
One garage didn’t have a clue but cost $42 and 4 hours of my Saturday morning.
Second garage guessed alignment/rims which didn’t solve the problem but cost $927 and 4 days. Subsequent attempts by mechanic to reproduce won’t work yet 2 days after rim/tire replacement, I had it happen again.
Third garage (Mazda) has no idea via phone explanation so I didn’t let them at it yet.
Somebody must have an idea!